Light absorption spectrum and magnetic behavior of CsMnF3 in fields to 300 kOe

An expenmental study is made of the effect of a magnetic field of intensity up to 300 kOe on the absorption spectrum of the antiferromagnet CsMnF3, in the region of the 6A1g→4A1g, 4Eg transition. It is shown that the behavior of band intensities and frequency intervals corresponds to changes in the magnetic Structure atypical of antiferromagnets because of differing exchange interaction in nonequivalent ion pairs. Consideration of the latter in interpretation of the spectrum allows establishment of the relationship with concrete sublattices of excitations responsible for various absorption bands and permits interpretation of one band as an exciton-two magnon band. A comparison is made between the experimentally observed increase in an external field of the intensity of purely exciton bands and the theory of two ion light absorption by group D6h4 antiferromagnets. Estimates of dipole moments in ion pairs give values of ∼ 10 cm−1.

Hali tarjima qilinmagan